Einstein developed two theories of relativity: special relativity and general relativity. Special relativity is a general theory about the structure of space and time, mass and energy, force, simultaneity, and much else. Every part of physics is touched by it. General relativity is "merely" a theory of gravity compatible with special relativity.

The Experimental Proof of the Special Theory of Relativity

The inteferometer, invented by Michelson, and implement by Michelson, Michelson and Morley, Morley and Miller, and Miller. Michelson tries to measure the speed of the earth, gives up, Lorenz points out that the sensitivity might not have been high enough. Michelson and Morley try. They give up. Morley and Miller try again. Then (now the 1920s) they do different experiments and Miller succeeds. He is the only one to succeed in getting an interferemeter to work inside a greenhouse on top of a mountain.

By the time Miller got his result, it was widely understood that special relativity produces a workable electromagnetic theory, and there were a number of, individually not very strong, "verifications" of special relativity. The Miller experiment, like the Michelson and Michelson-Morley experiments before it, was dismissed as an anomaly. That seems shocking to someone who believes scientists propaganda about decisive experiments, but, since we know that there is no such thing as a crucial experiment, we shouldn't be at all shocked or surprised. Collins and Pinch, in the afterword, use the metaphor of a rope.

What does require explanation is why scientists fool themselves about the historical facts about experiments. Scientists use textbook history, official history, and reviews to make sense of a field. Few realize, or care, that none of those is an accurate history of how science looks while it is being done.

General Relativity

According to Einstein, it followed from general relativity that gravity should bend light about twice as much as Newton's theory predicted. Eddington set about testing the prediction.

-- ShaughanLavine - 23 Apr 2009